Auro mercapto carboxylic acid and process of making same



' vention also Pate ted se i. 4, 1928.

. UNITED-STATES PATENT OFF-ICE.

scrrom' or nmmmm'rnnn, new we cacao manna-.01 3mmnnmrcmnomr-wnsr, 6mm, assrenons-ro rim nan ormmscnn rum nor ncrnnr (vomr. n. scnnamo),-ornnm.m, cumin;

-. AUBO'WO cmomrc ACID AND. PROQESS OI' MAKING- sum.

Io Drawing. Application fl ed February 10,1937, Serial 80.167350, and in Germany February 17, 1828.

Our invention refers to a new product being an aliphatic auro mercaptocarb lfylic acid or a metal salt thereof. The mincludes. the method of producsuch products. ealkali metal salts of the aliphatic auro mer'capto carboxylic acids are soluble in water., The constitution of the compounds corresponds to the general formula X-S-Au phatic carboxylic acid or alkali metal salt.

We obtain these new compounds by cansing an auric salt to act on an aliphatic merca tocarboxylic acidgin a neutral, acid or al aline medium with or without the-add tion of sulphur dioxide or a salt-thereof.

grains thiolacticacid are dissolved in a corresponding A 20 ccms acetic ether and a solution of 3.5

grams potassium auribromide is slowly added to ,the first solution drop by drop under cooling and stirring.- Stirring is continned until the solution has become altogether colorless,- whereupon the acetic etheris evaporated in vacuo,'the. residue boiled with water and filtered by suction andrmsedwith a little alcohol and ether. The residue consists of pure a-auro mercapto propiomc acid having the formula omen-coon By dissolving this compound in the required uantity of normal caustic soda solution an precipitation with alcohol we ob,-

tain the sodium salt, which-is preferably redissolved and to urify it.

his salt forms a.yellow1sh amorphous powder which is readily soluble in water, insoluble in organic solvents and contains 60.5 per cent gold (calculated percentage 60.8).

precipitated anew in order 1 v Example 2: A

14 grams eystein hydrochloride (hydro- .solution Has lost its color,

y of normal caustic soda.

wherein X stands for the radicle of an allacid) are dissolved in 150 ccms water. To

this solution are added 130 ccms of a. 4.4 per cent solution of sulphur dioxide. At 0 C. 525 ccms of a 10 per cent potassium auribromide solution are slowly introduced into the mixture under stirring. -When the the white powder, which has settled down is separated by suction and dissolved in t e uired quantit 's solution is filtered and. the fivefold ,volume of alcohol is added to preci itate the sodium salt, which is readily soluble in water, insoluble in alcohol and the usual solvents and contains 57 .5 per cent gold galculated precentage 58.1). It correspon to the formula,

The new compounds are distinguished by valuable therapeutical properties.

Various changes maybe made in the details disclosed in the foregoing specification without departing from the'invention or sacrificing t e advantages thereof. In the claims afl'ixed to this specification the term a radical of an aliphatic carboxylic acid is intended to mean univalent groups with an open chain of C-atoms, to which is I linked a carboxyl group, the typical hydrogen atom in which may also be replaced by a salt of an alkali metal;

We claim 1. As a new product a compound having the general formula X-SAu, wherein X is a radical of an aliphatic carboxylic compound, the alkali metal salts being soluble in water and having valuable therapeutical I 'dimolves n water, is insoluble in alcohol and other organic solvents and contains about 58 per cent gold. 

